U.S. patent application number 17/345596 was filed with the patent office on 2021-10-07 for intersection information distribution apparatus and intersection information distribution method.
The applicant listed for this patent is Panasonic Intellectual Property Corporation of America. Invention is credited to KENICHI ONO, NAGANORI SHIRAKATA, KOJI TAKINAMI, NOBORU YAMAMOTO.
Application Number | 20210312803 17/345596 |
Document ID | / |
Family ID | 1000005653205 |
Filed Date | 2021-10-07 |
United States Patent
Application |
20210312803 |
Kind Code |
A1 |
SHIRAKATA; NAGANORI ; et
al. |
October 7, 2021 |
INTERSECTION INFORMATION DISTRIBUTION APPARATUS AND INTERSECTION
INFORMATION DISTRIBUTION METHOD
Abstract
An intersection information distribution apparatus includes a
plurality of image capturers, one or more first wireless
communicators, a position estimator, and a controller. The
plurality of image capturers capture images in and around an
intersection. The one or more first wireless communicators perform
directional communication with a second wireless communicator
mounted on a vehicle. The position estimator estimates a position
of the vehicle in and around the intersection from a communication
state of the directional communication. The controller selects a
piece of data from among pieces of data of the images captured by
the plurality of image capturers on the basis of the estimated
position of the vehicle. The one or more first wireless
communicators transmit the selected piece of data to the second
wireless communicator of the vehicle.
Inventors: |
SHIRAKATA; NAGANORI;
(Kanagawa, JP) ; TAKINAMI; KOJI; (Kanagawa,
JP) ; ONO; KENICHI; (Hyogo, JP) ; YAMAMOTO;
NOBORU; (Tokyo, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Panasonic Intellectual Property Corporation of America |
Torrance |
CA |
US |
|
|
Family ID: |
1000005653205 |
Appl. No.: |
17/345596 |
Filed: |
June 11, 2021 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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15809848 |
Nov 10, 2017 |
11062597 |
|
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17345596 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G08G 1/0141 20130101;
G08G 1/09675 20130101; G08G 1/0116 20130101; G08G 1/096716
20130101; H04B 7/0695 20130101; G08G 1/096783 20130101; G06K
9/00785 20130101; H04W 84/00 20130101; H04B 7/0617 20130101; G08G
1/0112 20130101; G08G 1/04 20130101; G08G 1/096741 20130101; G08G
1/0145 20130101; H04B 7/088 20130101 |
International
Class: |
G08G 1/04 20060101
G08G001/04; H04B 7/06 20060101 H04B007/06; G08G 1/0967 20060101
G08G001/0967; G06K 9/00 20060101 G06K009/00; G08G 1/01 20060101
G08G001/01; H04W 84/00 20060101 H04W084/00 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 21, 2016 |
JP |
2016-225921 |
Claims
1. An apparatus comprising: capturing devices configured to capture
images in and around an intersection, the capturing devices being
one of video cameras, radars, or sensors; one or more first
millimeter-wave communicators configured to perform directional
communication with a second millimeter-wave communicator mounted on
a vehicle using a directional beam; and a circuit configured to:
estimate, in response to an area detector mounted on the vehicle
detecting entry of the vehicle into the intersection, a position of
the vehicle in and around the intersection on a basis of a
communication state of the directional beam used in the directional
communication; and select a piece of data from among pieces of data
corresponding to the images captured by the capturing devices on a
basis of the estimated position of the vehicle, wherein the one or
more first millimeter-wave communicators transmit the selected
piece of data to the second millimeter-wave communicator mounted on
the vehicle, and the area detector detects the intersection by
using a navigation system, a device capable of obtaining global
positioning system (GPS) information, or units for detecting
movement of the vehicle or communication state of a low speed
communicator.
2. The apparatus according to claim 1, wherein the circuit is
configured to estimate the position of the vehicle on a basis of a
direction of the directional beam used in the directional
communication.
3. The apparatus according to claim 1, wherein the capturing
devices capture images of different areas in and around the
intersection.
4. The apparatus according to claim 1, wherein in a case where the
estimated position of the vehicle is in a corner of the
intersection for making a left-hand turn, the selected piece of
data corresponds to an area in a left rear of the vehicle and to an
area in a right rear of the vehicle, and in a case where the
estimated position of the vehicle is at a center of the
intersection for making a right-hand turn, the selected piece of
data corresponds to an area behind another vehicle in an opposite
lane of the vehicle and to an area right of the vehicle.
5. The apparatus according to claim 1, wherein the circuit is
configured to estimate the position of the vehicle in and around
the intersection based on at least one of a strength, a
signal-to-noise ratio (SNR), or a signal-to-interference-plus-noise
ratio (SINK) of the direction beam.
6. The apparatus according to claim 1, wherein: the circuit is
further configured to: determine a lane in which the vehicle is
present and a direction of travel in and around the intersection
from the estimated position of the vehicle; and determine one or
more blind-spot areas of the vehicle on a basis of a result of the
determination of the lane and the direction of travel, and the
selecting includes selecting the piece of data from among pieces of
data corresponding to the images that are capturing images of the
one or more blind-spot areas on a basis of a result of the
determination of the one or more blind-spot areas.
7. A method comprising: capturing, by a plurality of image
capturers, images in and around an intersection; performing, by one
or more first millimeter-wave communicators, directional
communication with a second millimeter-wave communicator mounted on
a vehicle using a directional beam; estimating, in response to an
area detector mounted on the vehicle detecting entry of the vehicle
into the intersection, a position of the vehicle in and around the
intersection on a basis of a communication state of the directional
beam used in the directional communication; selecting a piece of
data from among pieces of data corresponding to the images captured
by the plurality of image capturers on a basis of the estimated
position of the vehicle; and transmitting, by the one or more first
millimeter-wave communicators, the selected piece of data to the
second millimeter-wave communicator of the vehicle, wherein the
area detector detects the intersection by using a navigation
system, a device capable of obtaining global positioning system
(GPS) information, or units for detecting movement of the vehicle
or communication state of a low speed communicator.
8. The method according to claim 7, wherein estimating the position
of the vehicle includes estimating the position of the vehicle on a
basis of a direction of the directional beam used in the
directional communication.
9. The method according to claim 7, wherein the pieces of data
corresponding to the images captured by the plurality of image
capturers are pieces of data of images of different areas in and
around the intersection.
10. The method according to claim 7, wherein in a case where the
estimated position of the vehicle is in a corner of the
intersection for making a left-hand turn, the selected piece of
data corresponds to an area in a left rear of the vehicle and to an
area in a right rear of the vehicle, and in a case where the
estimated position of the vehicle is at a center of the
intersection for making a right-hand turn, the selected piece of
data corresponds to an area behind another vehicle in an opposite
lane of the vehicle and to an area right of the vehicle.
11. The method according to claim 7, further comprising:
determining a lane in which the vehicle is present and a direction
of travel in and around the intersection from the estimated
position of the vehicle; and determining one or more blind-spot
areas of the vehicle on a basis of a result of the determination of
the lane and the direction of travel, wherein the selecting
includes selecting the piece of data from among pieces of data
corresponding to the images that are capturing images of the one or
more blind-spot areas on a basis of a result of the determination
of the one or more blind-spot areas.
12. An apparatus comprising: capturing devices configured to
capture images in and around an intersection, the capturing devices
being one of video cameras, radars, or sensors; one or more first
millimeter-wave communicators configured to perform directional
communication with a second millimeter-wave communicator mounted on
a vehicle using a directional beam; a processor; and a
non-transitory recording medium storing thereon a computer program
which, when executed by the processor, causes the processor to:
estimate, in response to an area detector mounted on the vehicle
detecting entry of the vehicle into the intersection, a position of
the vehicle in and around the intersection on a basis of a
communication state of the directional beam used in the directional
communication; and select a piece of data from among pieces of data
corresponding to the images captured by the capturing devices on a
basis of the estimated position of the vehicle, wherein the one or
more first millimeter-wave communicators transmit the selected
piece of data to the second millimeter-wave communicator mounted on
the vehicle, wherein the area detector detects the intersection by
using a navigation system, a device capable of obtaining global
positioning system (GPS) information, or units for detecting
movement of the vehicle or communication state of a low speed
communicator.
13. The apparatus according to claim 12, wherein the position of
the vehicle is estimated based on a direction of the directional
beam used in the directional communication.
14. The apparatus according to claim 12, wherein the capturing
devices capture images of different areas in and around the
intersection.
15. The apparatus according to claim 12, wherein in a case where
the estimated position of the vehicle is in a corner of the
intersection for making a left-hand turn, the selected piece of
data corresponds to an area in a left rear of the vehicle and to an
area in a right rear of the vehicle, and in a case where the
estimated position of the vehicle is at a center of the
intersection for making a right-hand turn, the selected piece of
data corresponds to an area behind another vehicle in an opposite
lane of the vehicle and to an area in right of the vehicle.
16. The apparatus according to claim 12, wherein: the computer
program, when executed by the processor, further causes the
processor to: determine a lane in which the vehicle is present and
a direction of travel in and around the intersection from the
estimated position of the vehicle; and determine one or more
blind-spot areas of the vehicle on a basis of a result of the
determination of the lane and the direction of travel, and the
selecting includes selecting the piece of data from among pieces of
data corresponding to the images that are capturing images of the
one or more blind-spot areas on a basis of a result of the
determination of the one or more blind-spot areas.
Description
BACKGROUND
1. Technical Field
[0001] The present disclosure relates to an intersection
information distribution apparatus and an intersection information
distribution method, and particularly relates to an apparatus and a
method for quickly distributing information, such as images of an
intersection and its surroundings, to a movable body, such as a
vehicle.
2. Description of the Related Art
[0002] As an intersection information distribution apparatus
according to the related art, an intersection information
distribution apparatus according to Japanese Patent No. 5204060
selects an antenna from among a plurality of directional antennas
in response to a request from a service application on the basis of
a distribution target area, a communication area, and a
transmission power associated in advance and uses the selected
antenna to distribute data of, for example, images of an
intersection and its surroundings to vehicles.
[0003] However, the intersection information distribution apparatus
according to Japanese Patent No. 5204060 does not take into
consideration an increase in the number of pieces of image data of
captured images, and therefore, it is difficult to distribute image
data useful for driving assistance at an intersection where
accidents frequently occur.
SUMMARY
[0004] In one general aspect, the techniques disclosed here feature
an intersection information distribution apparatus that includes a
plurality of image capturers, one or more first wireless
communicators, a position estimator, and a controller. The
plurality of image capturers capture images in and around an
intersection. The one or more first wireless communicators perform
directional communication with a second wireless communicator
mounted on a vehicle. The position estimator estimates a position
of the vehicle in and around the intersection from a communication
state of the directional communication. The controller selects a
piece of data from among pieces of data of the images captured by
the plurality of image capturers on the basis of the estimated
position of the vehicle. The one or more first wireless
communicators transmit the selected piece of data to the second
wireless communicator of the vehicle.
[0005] According to one aspect of the present disclosure, a piece
of information among a plurality of pieces of intersection
information can be distributed in accordance with the position of a
vehicle in or around an intersection.
[0006] It should be noted that general or specific embodiments may
be implemented as a system, a method, an integrated circuit, a
computer program, a storage medium, or any selective combination
thereof.
[0007] Additional benefits and advantages of the disclosed
embodiments will become apparent from the specification and
drawings. The benefits and/or advantages may be individually
obtained by the various embodiments and features of the
specification and drawings, which need not all be provided in order
to obtain one or more of such benefits and/or advantages.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is a diagram illustrating an example of an
intersection information distribution system according to an
embodiment of the present disclosure;
[0009] FIG. 2 is a flowchart illustrating an example operation flow
of an intersection information distribution system;
[0010] FIG. 3A is a flowchart illustrating an example operation
flow of a roadside apparatus;
[0011] FIG. 3B is a flowchart illustrating an example operation
flow of an onboard apparatus;
[0012] FIG. 4 is a diagram illustrating an example arrangement in
and around an intersection;
[0013] FIG. 5 is a diagram illustrating an example communication
area;
[0014] FIG. 6 is a diagram illustrating an example system operation
for a vehicle traveling straight ahead;
[0015] FIG. 7 is a diagram illustrating an example system operation
for a vehicle making a right-hand turn;
[0016] FIG. 8 is a diagram illustrating an example system operation
for a vehicle making a left-hand turn; and
[0017] FIG. 9 is a diagram illustrating an example handover
operation for a vehicle making a right-hand turn.
DETAILED DESCRIPTION
[0018] Examples of information content related to driving
assistance for vehicles (hereinafter referred to as driving
assistance information) include image data of high-resolution
images captured at various angles, sensing data from sensors (for
example, radars), 3D map data, and sensing data for automatic
driving. The volume of such driving assistance information is
expected to increase.
[0019] In order to broadcast and distribute all pieces of driving
assistance information to a plurality of vehicles in and around an
intersection at which accidents frequently occur, a large number of
conditions, such as the communication band, the processing time,
and radio interference, need to be taken into consideration, and it
is desirable to distribute necessary driving assistance information
to vehicles that need information.
[0020] Driving assistance information needed differs depending on
the position of a vehicle in or around the intersection, namely,
whether the vehicle is traveling straight ahead, making a
right-hand turn, or making a left-hand turn, or a lane in which the
vehicle is present, for example.
[0021] Accordingly, regarding distribution of driving assistance
information, a solution for achieving both position estimation of a
distribution target vehicle in and around an intersection and
high-speed wireless communication is under study.
Embodiment
[0022] Hereinafter, an embodiment of the present disclosure will be
described with reference to the drawings.
[0023] FIG. 1 is a block diagram illustrating a configuration of an
intersection information distribution system 100. The intersection
information distribution system 100 includes a roadside apparatus
(also referred to as an intersection information distribution
apparatus) 101 and an onboard apparatus 102. The roadside apparatus
101 includes a controller 1011, a low-speed communicator 1012, a
plurality of millimeter-wave communicators 1013, a storage unit
1014, a position estimator 1015, a plurality of image capturers
1016, and an external interface (I/F) 1017. The onboard apparatus
102 includes a controller 1021, a low-speed communicator 1022, a
millimeter-wave communicator 1023, a storage unit 1024, an area
detector 1025, a user interface (UI) 1026, and an external I/F
1027.
[0024] The roadside apparatus (intersection information
distribution apparatus) 101 transmits to the onboard apparatus 102
via the plurality of millimeter-wave communicators 1013 driving
assistance information obtained by the plurality of image capturers
1016 capturing images of areas that are blind spots around an
intersection. For example, areas that are blind spots differ
depending on the position of the vehicle, and driving assistance
information needed differs accordingly. Therefore, the position
estimator 1015 estimates the position of the onboard apparatus 102,
and the roadside apparatus 101 selects and transmits a piece of
driving assistance information needed from among pieces of driving
assistance information stored in the storage unit 1024 in
accordance with the position of the vehicle.
[0025] The onboard apparatus 102 processes driving assistance
information received via the millimeter-wave communicator 1023 into
information needed for assisting the driver and communicates the
information to the driver via the UI 1026.
[0026] The low-speed communicators 1012 and 1022 perform wireless
communication with each other at a low communication speed by using
a communication system for a wide communication area. As the
communication system, Zigbee, Bluetooth (registered trademark),
Dedicated Short Range Communication (DSRC), Wi-Fi, such as IEEE
802.11p or IEEE 802.11/b/g/a/n/ac, or a cellular system, such as 3G
or Long Term Evolution (LTE), can be used, for example.
[0027] Here, the low communication speed is a communication speed
that is lower than that of the millimeter-wave communicators 1013
and 1023 and ranges, for example, from several tens of kbps to
several tens of Mbps or so. The wide communication area is an area
that is wider than that of the millimeter-wave communicators 1013
and 1023 and is a communication area ranging, for example, from
several tens of meters to several tens of kilometers. The low-speed
communicators 1012 and 1022 need not have a low communication speed
and need to have a communication area wider than that of the
millimeter-wave communicators 1013 and 1023.
[0028] The millimeter-wave communicators 1013 and 1023 perform
wireless communication with each other at a high communication
speed by using a communication system for a narrow communication
area. As the communication system, IEEE 802.11ad/WiGig using a
millimeter wave can be used, for example. Here, the high
communication speed needs to be a communication speed that is
higher than that of the low-speed speed communicators 1012 and 1022
and ranges, for example, from several hundreds of Mbps to several
Gbps or so.
[0029] The narrow communication area is an area that is narrower
than that of the low-speed communicators 1012 and 1022 and is a
communication area of, for example, several meters or so. The
millimeter-wave communicators 1013 and 1023 each have a plurality
of antennas and perform directional control by using beamforming.
The millimeter-wave communicators 1013 and 1023 need not have a
narrow communication area and need to have a communication speed
higher than that of the low-speed communicators 1012 and 1022.
[0030] The storage units 1014 and 1024 store driving assistance
information and so on and are each constituted by, for example, a
volatile memory, a nonvolatile memory, a solid state drive (SSD),
or a hard disk drive (HDD). As the driving assistance information,
data of moving images captured by using video cameras and digitized
at various resolutions, digital data which is obtained by radars
and sensors performing measurements and from which distances and
directions are obtained, 3D moving image data obtained by combining
the above-described pieces of data, or data that includes map
information created in advance as 3D data can be used, for
example.
[0031] The image capturers 1016 are provided for generating driving
assistance information. As the image capturers 1016, video cameras
used to capture images of a plurality of blind-spot areas around an
intersection, radars for measuring a plurality of blind-spot areas
around an intersection, sensors for detecting vehicles in lanes,
and sensors for detecting persons on sidewalks can be used, for
example. The plurality of image capturers 1016 are installed at
various positions in and around an intersection so as to allow
capturing of images of a large number of blind-spot areas.
[0032] The position estimator 1015 estimates the position of the
onboard apparatus 102, which is a communication partner. In order
to estimate the position, the result of directional control
performed by the millimeter-wave communicators 1013, changes in the
communication state of the millimeter-wave communicators 1013, and
changes in the communication state of the low-speed communicator
1012 can be used, for example. As the changes in the communication
state, changes in the reception quality during communication (the
received radio wave strength, received signal strength indicator
(RSSI), signal-to-noise ratio (SNR),
signal-to-interference-plus-noise ratio (SINR), and packet error
rate) can be used, for example. Position estimation using
information obtained by the millimeter-wave communicators 1013
covers, for example, areas in and around an intersection, and
position estimation using information obtained by the low-speed
communicator 1012 covers, for example, a wider area that includes
an intersection.
[0033] The external I/F 1017 is an interface for connection with
external devices. The external I/F 1017 connects with an external
network, such as the Internet, via, for example, an Ethernet line
or a dedicated line. The external I/F 1017 is not limited to a
wired interface, and a wireless connection interface may be
used.
[0034] The controller 1011 controls each component of the roadside
apparatus 101. The controller 1011 is typically constituted by a
central processing unit (CPU) and a software program and may be
constituted by a hardware unit, such as a dedicated large-scale
integration (LSI) circuit or a field-programmable gate array
(FPGA). The controller 1011 and each component need not be
connected via a wired connection and may be connected via a
wireless connection.
[0035] The area detector 1025 detects an intersection area in which
the roadside apparatus 101 is present. The area detector 1025 may
detect an intersection by using a generally available navigation
system or a generally available device capable of obtaining global
positioning system (GPS) information. The area detector 1025 may
include units for detecting movement of the onboard apparatus 102,
such as an acceleration sensor, a gyro sensor, and a geomagnetism
sensor, not illustrated and may detect whether the onboard
apparatus 102 moves into an intersection area or moves out of an
intersection area by using output from the sensors. Further, the
area detector 1025 may detect an intersection area by using
information regarding the communication state of the low-speed
communicators 1012 and 1022.
[0036] The UI 1026 displays driving assistance information to the
driver of the vehicle and is used to perform operations for driving
assistance. The UI 1026 may be constituted by a display panel, a
light emitting diode (LED), a touch panel, a key pad, a keyboard, a
switch, and/or an audio input/output. Alternatively, the UI 1026
may be constituted by the user interface of a navigation system
installed in the vehicle or the dashboard or a display panel in
front of the driver's seat. In a case of a vehicle capable of
automatic driving, the UI 1026 may be constituted by an interface
of a controller for automatic driving.
[0037] The external I/F 1027 is an interface for connection with
external devices. The external I/F 1027 may be constituted by, for
example, an Ethernet line or a dedicated line, a network interface,
such as a controller area network (CAN) in the vehicle, or a
peripheral device interface, such as an RS232C interface or a USB
interface. The external I/F 1027 need not be a wired interface, and
a wireless connection interface may be used.
[0038] The controller 1021 controls each component of the onboard
apparatus 102. The controller 1021 is typically constituted by a
CPU and a software program and may be constituted by a hardware
unit, such as a dedicated LSI circuit or an FPGA. The controller
1021 and each component need not be connected via a wired
connection and may be connected via a wireless connection.
[0039] FIG. 2 is a flowchart illustrating an example of driving
assistance information distribution performed in the intersection
information distribution system 100. Here, an operation of the
entire system is described.
[0040] In step S201, the area detector 1025 of the onboard
apparatus 102 detects an entry into an intersection area.
[0041] In step S202, the onboard apparatus 102 makes preparations
for millimeter-wave communication between the onboard apparatus
102, which has entered the intersection area, and the roadside
apparatus 101. For example, the onboard apparatus 102 turns on the
power of the millimeter-wave communicator 1023 and searches for a
millimeter-wave communication area.
[0042] In step S203, the millimeter-wave communicators 1013 and
1023 perform beamforming training for millimeter-wave communication
and establish a radio link. The millimeter-wave communicators 1013
and 1023 each perform directional control to select a beam
direction in which optimal reception quality for communication can
be obtained.
[0043] In step S204, the position estimator 1015 of the roadside
apparatus 101 estimates the position of the onboard apparatus 102.
The position estimator 1015 obtains position information about the
estimated position in the intersection area from information
regarding the beam direction obtained as a result of the
beamforming training.
[0044] In step S205, the position estimator 1015 of the roadside
apparatus 101 determines the lane and the direction of travel in
and around the intersection from the estimated position of the
onboard apparatus 102 and determines blind-spot areas of the
vehicle in which the onboard apparatus 102 is mounted on the basis
of the result of determination.
[0045] In step S206, the controller 1011 prioritizes and selects a
predetermined number of the image capturers 1016 among the
plurality of image capturers 1016 that are capturing images of the
determined blind-spot areas on the basis of the result of
determination by the position estimator 1015.
[0046] In step S207, the millimeter-wave communicators 1013
distribute driving assistance information regarding the blind-spot
areas for which images have been captured by the selected image
capturers 1016 to the onboard apparatus 102.
[0047] In step S208, the onboard apparatus 102 processes the
driving assistance information received via the millimeter-wave
communicator 1023 as needed and displays the resulting information
to the driver via the UI 1026 for use in driving assistance.
[0048] In step S209, the area detector 1025 of the onboard
apparatus 102 detects an exit from the intersection area. Steps
S203 to S209 are repeated during a period in which the onboard
apparatus 102 is staying in the intersection area.
[0049] In step S210, in case where the onboard apparatus 102 has
exited from the intersection area, the millimeter-wave communicator
1023 disconnects the millimeter-wave link and ends the intersection
information distribution operation.
[0050] FIG. 4 illustrates an example arrangement of the roadside
apparatus 101 and an example position relationship with a vehicle
on which the onboard apparatus 102 is mounted, in and around an
intersection. A process flow of the roadside apparatus 101 and that
of the onboard apparatus 102 are described below.
[0051] FIG. 4 illustrates an example arrangement in and around an
intersection. FIG. 4 is an overhead view of an intersection around
which a vehicle keeps to the left side of the road and at which
roads cross each other. Three millimeter-wave communicators 1013-1
to 1013-3 are installed in the corners of the intersection on poles
at a height of about 3 to 5 meters that is substantially equal to a
height at which traffic signals are installed. Further, five video
cameras (image capturers 1016-1 to 1016-5) are also installed on
poles and capture images of the states of the roads in different
directions.
[0052] The millimeter-wave communicators 1013 and the image
capturers 1016 of the roadside apparatus 101 are connected to one
another via wired or wireless connections not illustrated, and the
other components are housed in the roadside apparatus 101. The
onboard apparatus 102 is mounted on a target vehicle 401 on the
road.
[0053] When the target vehicle 401 enters the intersection, the
intersection information distribution system starts operating. In
FIG. 4, the number of the millimeter-wave communicators 1013 is
three, and the number of the image capturers 1016 is five; however,
the number of the millimeter-wave communicators 1013 and the number
of the image capturers 1016 are not limited to these and can be
adjusted in accordance with the structure of the intersection and
the system design specifications.
[0054] FIG. 3A is a flowchart illustrating a process flow of the
roadside apparatus 101, and FIG. 3B is a flowchart illustrating a
process flow of the onboard apparatus 102. Steps S3101 to S3112
correspond to the process flow of the roadside apparatus 101, and
steps S3201 to S3209 correspond to the process flow of the onboard
apparatus 102.
[0055] In step S3201, the onboard apparatus 102 determines whether
the onboard apparatus 102 has entered an intersection area 501 (see
FIG. 5) on the basis of output from the area detector 1025. In case
where the onboard apparatus 102 has not entered the intersection
area 501 (No in step S3201), the onboard apparatus 102 repeats step
S3201. In case where the onboard apparatus 102 has entered the
intersection area 501 (Yes in step S3201), the flow proceeds to
step S3202.
[0056] In step S3101, the roadside apparatus 101 periodically (for
example, at intervals of 100 msec) transmits to access point (AP)
areas of the roadside apparatus 101 via the millimeter-wave
communicators 1013 beacons indicating, for example, the address of
the roadside apparatus 101 and information necessary for
connection. In step S3102, the roadside apparatus 101 determines
whether a connection request has been made from the onboard
apparatus 102.
[0057] In step S3202, the onboard apparatus 102 turns on the power
of the millimeter-wave communicator 1023 and searches for a
millimeter-wave communication area. Specifically, the
millimeter-wave communicator 1023 scans beacons transmitted from
the millimeter-wave communicators 1013. In step S3203, in case
where the millimeter-wave communicator 1023 has detected a beacon,
the flow proceeds to step S3204. In case where the millimeter-wave
communicator 1023 has not detected a beacon (No in step S3203), the
onboard apparatus 102 repeats step S3203. This operation may be
terminated in response to the process being stopped by a timer not
illustrated or in response to detection of an exit from the
intersection area.
[0058] In step S3204, the onboard apparatus 102 makes a connection
request to the millimeter-wave communicator 1013 of the roadside
apparatus 101 that has transmitted the beacon received by the
millimeter-wave communicator 1023. For example, the millimeter-wave
communicator 1023 includes the address of the onboard apparatus 102
in a control packet for requesting connection as the address of the
connection destination and transmits the control packet.
[0059] In step S3102, in case where the roadside apparatus 101
receives the control packet for requesting connection from the
onboard apparatus 102 via the millimeter-wave communicator 1013 and
determines that a connection request has been made (Yes in step
S3102), the flow proceeds to step S3103.
[0060] In step S3103, the roadside apparatus 101 allows the
millimeter-wave communicator 1013 to connect with the onboard
apparatus 102. For example, the millimeter-wave communicator 1013
includes the address of the roadside apparatus 101 in a control
packet for allowing connection as the address of the connection
destination and transmits the control packet, and the
millimeter-wave communicator 1023 of the onboard apparatus 102
receives the control packet. The connection process is performed
accordingly, and a radio link is established.
[0061] The roadside apparatus 101 and the onboard apparatus 102
each perform beamforming training for selecting a beam used in
communication in step S3104 and in step S3205, respectively. The
millimeter-wave communicators 1013 and 1023 each select a beam
having the highest reception quality by using, for example, sector
level sweep (SLS), which is a protocol used in IEEE 802.11ad/WiGig,
and feeding back to each other the result of reception of a
plurality of training packets transmitted using different
beams.
[0062] For example, in a case where the target vehicle 401 performs
beamforming training with the millimeter-wave communicator 1013-3,
as illustrated in FIG. 6, the millimeter-wave communicator 1013-3
selects the beam 606 and the millimeter-wave communicator 1023 of
the target vehicle 401 selects the beam 607 to thereby perform
millimeter-wave communication having good reception quality.
[0063] The beamforming training in step S3104 and that in step
S3205 are periodically performed during a period in which the
target vehicle 401 is staying in the intersection area, and
selected beams change moment by moment in accordance with the
position of the target vehicle 401.
[0064] For example, in a case where the target vehicle 401 is
located at the center of the intersection for making a right-hand
turn, as illustrated in FIG. 7, the millimeter-wave communicator
1013-1 selects the beam 707, and the millimeter-wave communicator
1023 of the target vehicle 401 selects the beam 708 in the left
front direction. For example, in a case where the target vehicle
401 is located in the corner of the intersection for making a
left-hand turn, as illustrated in FIG. 8, the millimeter-wave
communicator 1013-1 selects the beam 805, and the millimeter-wave
communicator 1023 of the target vehicle 401 selects the beam 806 in
the front direction.
[0065] In step S3105, the position estimator 1015 of the roadside
apparatus 101 estimates the position of the target vehicle 401 from
the result of beamforming training. In FIG. 6, FIG. 7, and FIG. 8,
combinations of selected beams differ depending on the position of
the target vehicle 401, and the position estimator 1015 estimates
the position of the target vehicle 401 on the basis of the beam
selected by the millimeter-wave communicator 1013-1 or 1013-3.
[0066] For example, on the basis of the combination of the beam 707
and the beam 708 illustrated in FIG. 7, the position estimator 1015
can estimate that the target vehicle 401 is highly likely to be
located in a beam area 503-3 among beam areas 503-1 to 503-6
illustrated in FIG. 5. Further, the position estimator 1015 can
estimate the position of the target vehicle 401 with a higher
accuracy by estimating the distance on the basis of the reception
quality (for example, the received radio wave strength, RSSI, SNR,
and SINR) in communication using beamforming and further estimating
the angle of arrival of the radio wave.
[0067] Alternatively, the position estimator 1015 can combine the
results of beamforming training by the millimeter-wave
communicators 1013-1 to 1013-3 and estimate the position on the
basis of the combinations of the beams.
[0068] In step S3106, the position estimator 1015 of the roadside
apparatus 101 determines blind-spot areas of the target vehicle 401
on the basis of the estimated position of the target vehicle 401.
The blind-spot areas change in accordance with the position at
which the target vehicle 401 is present, the lane, and the
direction of travel.
[0069] For example, in FIG. 6, the target vehicle 401 is in the
straight through lane and enters the intersection, and therefore,
the area 601 on the left-hand road and the area 602 on the
right-hand road are blind-spot areas. The area 601 is behind the
vehicle 603, and therefore, is a non-visible area. Regarding the
area 602, when the target vehicle 401 enters the intersection, the
vehicle 604 and the pedestrian 605 in the area 602 are located to
the right of the target vehicle 401 and disappear from the driver's
sight accordingly. Therefore, attention needs to be paid.
[0070] In FIG. 7, the area 701 behind the vehicle 703 in the
opposite lane and the area 702 located to the right of the target
vehicle 401 are blind-spot areas. The pedestrian 704 is outside the
area 701, and the vehicle 705 and the pedestrian 706 are located in
the area 702. In FIG. 8, the area 801 in the left rear direction of
the target vehicle 401 that is making a left-hand turn and the area
802 on the right-hand road in the right rear direction of the
target vehicle 401 that is making a left-hand turn are blind-spot
areas. The pedestrian 803 is located in the area 801, and the
vehicle 804 is located in the area 802.
[0071] In step S3107, the controller 1011 of the roadside apparatus
101 prioritizes and selects the image capturers 1016 that are
capturing images of blind-spot areas when the target vehicle 401 is
located at the estimated position from among the plurality of image
capturers 1016. For example, in FIG. 6, the image capturer 1016-3
capturing an image of the area 601 and the image capturer 1016-5
capturing an image of the area 602 are assigned a high priority
from the viewpoint of driving assistance for the target vehicle
401, and therefore, are selected. In FIG. 7, the image capturer
1016-4 capturing an image of the area 701 and the image capturer
1016-2 capturing an image of the area 702 are selected. In FIG. 8,
the image capturer 1016-1 capturing an image of the area 801 and
the image capturer 1016-5 capturing an image of the area 802 are
selected.
[0072] In step S3108, the roadside apparatus 101 transmits data
obtained by the selected image capturers 1016, that is, driving
assistance information regarding the blind-spot areas for which
images have been captured by the selected image capturers 1016, to
the onboard apparatus 102 via the millimeter-wave communicator
1013.
[0073] In step S3206, the onboard apparatus 102 receives
intersection captured-image data (driving assistance information)
transmitted from the millimeter-wave communicator 1013 via the
millimeter-wave communicator 1023.
[0074] In step S3207, the onboard apparatus 102 processes the
received data (driving assistance information) as needed and uses
in driving assistance, namely, displays the resulting data to the
driver, for example. The driving assistance information may be
processed by the controller 1011 or by the UI 1026 or may be
processed by an information processor not illustrated via the
external I/F 1027.
[0075] The processing performed as needed includes, for example, an
operation of converting the viewpoint of a captured image of a
blind-spot area to a viewpoint that does not make the driver feel
unnatural. Alternatively, an operation of detecting, recognizing,
and determining a target object that is an obstacle from a captured
image of a blind-spot area, and thereafter, communicating the
obstacle to the driver via the UI 1026 may be performed.
Communicating such information can allow safer driving by the
driver.
[0076] In step S3109, the position estimator 1015 of the roadside
apparatus 101 determines whether the target vehicle 401 has exited
from the communication area of one of the millimeter-wave
communicators 1013 and has entered the communication area of
another one of the millimeter-wave communicators 1013. For example,
in FIG. 9, the target vehicle 401-1 performs communication in the
AP area 502 of the millimeter-wave communicator 1013-1. At this
time, the millimeter-wave communicator 1013-1 selects the beam 707,
and the millimeter-wave communicator 1023 of the target vehicle
401-1 selects the beam 708.
[0077] Thereafter, the millimeter-wave communicator 1023 of the
target vehicle 401-2, which is the target vehicle after movement,
has difficulty in communicating with the millimeter-wave
communicator 1013-1 using the beam 708. The roadside apparatus 101
and the onboard apparatus 102 periodically perform beamforming
training (step S3104 and step S3205) to determine the state where
communication becomes difficult due to movement of the vehicle.
Accordingly, the possibility of the target vehicle 401 exiting from
the AP area can be determined.
[0078] In case where the position estimator 1015 of the roadside
apparatus 101 determines that the possibility of an exit from the
AP area is high (Yes in step S3109), the flow proceeds to step
S3110. In case where the position estimator 1015 of the roadside
apparatus 101 determines that the target vehicle is staying within
the same AP area (No in step S3109), the flow proceeds to step
S3111.
[0079] In step S3110, the roadside apparatus 101 performs a
handover process between AP areas via the plurality of
millimeter-wave communicators 1013. For example, in FIG. 9, the
roadside apparatus 101 changes connection information for the
millimeter-wave communicator 1023 of the target vehicle 401,
namely, changes the connection destination from the millimeter-wave
communicator 1013-1 to the millimeter-wave communicator 1013-2 of
the roadside apparatus 101.
[0080] In FIG. 9, the target vehicle 401 moves from the AP area 502
to the AP area 901 while making a right-hand turn. The AP area 901
is the communication area of the millimeter-wave communicator
1013-2. When a handover is performed, the target vehicle 401
performs beamforming training for connection with the
millimeter-wave communicator 1013-2. Accordingly, the
millimeter-wave communicator 1013-2 selects the beam 902, and the
millimeter-wave communicator 1023 of the target vehicle 401 selects
the beam 903 to thereby establish a radio link.
[0081] In step S3111, the position estimator 1015 of the roadside
apparatus 101 determines whether the target vehicle 401 has exited
from the intersection area. In case where the target vehicle 401
has exited from the intersection area (Yes in step S3111), the flow
proceeds to step S3112. In case wherethe target vehicle 401 has not
exited from the intersection area (No in step S3111), the flow
returns to step S3104, and the process is repeated.
[0082] In step S3208, the area detector 1025 of the onboard
apparatus 102 also determines whether the onboard apparatus 102 has
exited from the intersection area. In case where the onboard
apparatus 102 has exited from the intersection area (Yes in step
S3208), the flow proceeds to step S3209. In case where the onboard
apparatus 102 has not exited from the intersection area (No in step
S3208), the flow returns to step S3205, and the process is
repeated.
[0083] In step S3112, the roadside apparatus 101 disconnects the
millimeter-wave link with the target vehicle via the
millimeter-wave communicator 1013.
[0084] In step S3209, the onboard apparatus 102 disconnects the
millimeter-wave link with the roadside apparatus 101 via the
millimeter-wave communicator 1023. The onboard apparatus 102 turns
off the power of the millimeter-wave communicator 1023 to decrease
power consumption.
[0085] The flow of the series of processes has been chronologically
described with reference to the flowcharts in FIGS. 3A and 3B. The
series of processes is performed for a plurality of target
vehicles, and therefore, each process may be performed by a
plurality of controllers in parallel.
Example Applications
[0086] The embodiment described above can be applied to example
operations described below.
[0087] On the basis of data of moving images captured by a
high-precision image capturing device of the roadside apparatus,
the controller 1011 or an information processor, not illustrated,
connected to the roadside apparatus via the external I/F 1017
detects and identifies one or more objects present in and/or around
an intersection, and the roadside apparatus distributes driving
assistance information including information about the objects (for
example, information about whether the objects are vehicles,
pedestrians, or obstacles) to the onboard apparatus.
[0088] The onboard apparatus mounted in a vehicle that is
approaching an intersection transmits position information about
the vehicle obtained by a satellite positioning system, such as a
global navigation satellite system (GNSS), to the roadside
apparatus via low-speed wireless communication, such as cellular
communication, before the vehicle enters the intersection. In a
case of receiving preliminary information from the onboard
apparatus, the roadside apparatus expects the vehicle to enter the
intersection and starts capturing images in and around the
intersection at the timing when the vehicle enters the
intersection.
[0089] The onboard apparatus mounted on a vehicle that is
approaching an intersection transmits in advance position
information about the vehicle obtained by using retained map
information, such as a dynamic map, to the roadside apparatus via
low-speed wireless communication, such as cellular communication,
before the vehicle enters the intersection. In a case of receiving
preliminary information from the onboard apparatus, the roadside
apparatus expects the vehicle to enter the intersection and starts
capturing images in and around the intersection at the timing when
the vehicle enters the intersection.
[0090] In a case where the low-speed communicator of the roadside
apparatus receives a radio wave of, for example, Bluetooth Low
Energy (BLE) transmitted from a mobile device or the like carried
by a person present in or around an intersection, the image
capturers of the roadside apparatus start capturing images of the
intersection and its surroundings, and the controller 1011 or an
information processor, not illustrated, connected to the roadside
apparatus via the external I/F 1017 detects and identifies the
person present in or around the intersection. The millimeter-wave
communicator of the roadside apparatus communicates driving
assistance information including the result of detection and
identification to the onboard apparatus in or around the
intersection.
[0091] In a case where the roadside apparatus determines that a
warning needs to be issued in and around the intersection on the
basis of at least one of the result of detection and identification
of data from the image capturers, the preliminary information from
the vehicle received by the low-speed communicator, and the radio
wave from the mobile device carried by the person (for example, in
a case where an object that is traveling in a direction at a speed
significantly different from those in the usual traffic condition
is identified), the roadside apparatus distributes driving
assistance information in which the priority levels of the
blind-spot areas are changed to the onboard apparatus in or around
the intersection.
[0092] In a case where a vehicle in which a rear detector not
illustrated in the onboard apparatus 102 in FIG. 1 is mounted is
located in or around an intersection and is detecting objects in
the rear detection area, the UI 1026 preferentially displays
rear-detection information. In a case where the objects move out of
the rear detection area, the UI 1026 preferentially displays
driving assistance information received from the roadside
apparatus.
[0093] The embodiment has been described above with reference to
the drawings; however, the present disclosure is not limited to the
above-described embodiment. It is obvious that a person skilled in
the art can conceive various modifications and alterations within
the scope set forth in the claims, and it is understood that such
modifications and alternations also fall within the technical scope
of the present disclosure, as a matter of course. Further, any
components in the above-described embodiment may be combined as
appropriate without departing from the spirit of the present
disclosure.
[0094] In the above-described embodiment, the example configuration
of the present disclosure in which hardware units are used has been
described; however, the present disclosure can be implemented by
using software in cooperation with hardware.
[0095] The functional blocks used in the description of the
above-described embodiment are typically implemented as an LSI
circuit, which is an integrated circuit having an input terminal
and an output terminal. The integrated circuit controls the
functional blocks used in the description of the above-described
embodiment and may have an input and an output. Each of the
functional blocks may be implemented as a single chip, or some or
all of the functional blocks may be integrated into a single chip.
Although the integrated circuit is called an LSI circuit here, the
integrated circuit may be called an IC, an LSI circuit, a super LSI
circuit, or an ultra LSI circuit depending on the difference in the
degree of integration.
[0096] Further, the technique for circuit integration is not
limited to LSI, and circuit integration may be implemented by using
a dedicated circuit or a general-purpose processor. An FPGA that is
programmable after manufacturing the LSI, or a reconfigurable
processor for which connections and settings of circuit cells
within the LSI can be reconfigured may be used.
[0097] In a case where a technique for circuit integration that
replaces LSI emerges with the advancement of semiconductor
technology or on the basis of any technology that is separately
derived, the functional blocks may be integrated by using the
technique, as a matter of course. Application of, for example,
biotechnology is possible.
[0098] Various aspects of the embodiment of the present disclosure
include the following.
[0099] An intersection information distribution apparatus according
to a first aspect of the present disclosure includes: a plurality
of image capturers that capture images in and around an
intersection; one or more first wireless communicators that perform
directional communication with a second wireless communicator
mounted on a vehicle; a position estimator that estimates a
position of the vehicle in and around the intersection from a
communication state of the directional communication; and a
controller that selects a piece of data from among pieces of data
of the images captured by the plurality of image capturers on the
basis of the estimated position of the vehicle. The one or more
first wireless communicators transmit the selected piece of data to
the second wireless communicator of the vehicle.
[0100] An intersection information distribution apparatus according
to a second aspect of the present disclosure is the intersection
information distribution apparatus according to the first aspect in
which the position estimator estimates the position of the vehicle
on the basis of directions of directional beams used by the first
wireless communicators.
[0101] An intersection information distribution apparatus according
to a third aspect of the present disclosure is the intersection
information distribution apparatus according to the first aspect in
which the plurality of image capturers capture images of different
areas in and around the intersection.
[0102] An intersection information distribution method according to
a fourth aspect of the present disclosure includes: capturing
images by a plurality of image capturers in and around an
intersection; performing directional communication by a second
wireless communicator mounted on a vehicle and by one or more first
wireless communicators of an intersection information distribution
apparatus; estimating a position of the vehicle in and around the
intersection from a communication state of the directional
communication; selecting a piece of data from among pieces of data
of the images captured by the plurality of image capturers on the
basis of the estimated position of the vehicle; and transmitting
the selected piece of data to the second wireless communicator of
the vehicle.
[0103] An intersection information distribution method according to
a fifth aspect of the present disclosure is the intersection
information distribution method according to the fourth aspect in
which the position of the vehicle is estimated on the basis of
directions of directional beams used by the first wireless
communicators.
[0104] An intersection information distribution method according to
a sixth aspect of the present disclosure is the intersection
information distribution method according to the fourth aspect in
which the pieces of data of the images captured by the plurality of
image capturers are pieces of data of images of different areas in
and around the intersection.
[0105] The present disclosure is preferably used in a mobile
communication system.
* * * * *